PHILADELPHIA -- The Eagles' offensive line has given up just five sacks during the team’s four-game winning streak. The unit has stood firm, despite the challenges that have come with facing dominant pass rushers like Aaron Donald, J.J. Watt, Ryan Kerrigan and Khalil Mack over the last month.

The Eagles have been prepared for their All-Pro adversaries largely due to the efforts of rookie defensive lineman Joe Ostman, an undersized edge rusher from a small town with a population of around 2,500 residents.

The St. Ignace, Mich. native spent the entire season on the practice squad, mimicking several different pass rushers during the weeks leading up to notable clashes.

Last week, the Central Michigan alum performed as Mack, donning his No. 52 jersey and moving around the formation accordingly. His work as a sparring partner helped the Eagles' offensive line prepare for Mack’s timing and versatility.

Mack produced just two quarterback hits during the Eagles' 16-15 wild-card round win over the Chicago Bears on Sunday. He stood out as a run defender but was unable to take advantage of his pass-rushing skills.

Ostman did such a good job replicating the All-Pro’s play that the offensive line was able to keep Mack contained.

“He’s just a guy that has all the tools,” Ostman said last week, regarding his role as Mack. He has “all of the tools of a pass rusher and he’s smart too ... He’s got go-to moves, so he’s a tough guy to stop.”

Ostman’s main job in practice is to make the offensive line better. He performs tasks based on weekly challenges.

One week, he could be standing up to rush like Mack. The next week, he could have his hand in the dirt like Watt.

“He has busted his tail all season long,” offensive coordinator Mike Groh said Tuesday, regarding Ostman’s work in practice. “He’s a better player because of the way he approaches practice each and every day. Embraces the number or jersey we put on him and we’ve played some excellent pass rushers over the stretch of games here. He’s usually been that guy.”

While Ostman spends most of his time mirroring all-stars, he is also learning how to become a professional pass rusher in his own right. The rookie receives plenty of opportunities to learn in practice and team meetings.

“Across our offensive line there’s a lot of All-Pro players and high-caliber players, so it’s been a good year [to compete] and I’m just going to keep working and keep at it,” Ostman said in Week 17.

As Ostman helps the Eagles during their latest run, he is also preparing himself for the competition of the upcoming offseason. He hopes to earn a spot on the active roster next season with a strong performance during training camp this summer.

"I think it’ll be huge for me just having the [practice squad] experience at this level,” Ostman said. “Being able to compete at this level and just come to work every day and get better. I’m just going to keep working hard and when that opportunity comes I’ll be ready.”